Are More 'Vitamins' in The Feed the Better?

Vitamin, also known as vitamin, is a life-sustaining substance, is a kind of trace organic substances necessary to maintain the normal physiological function and life activities of animals, and is also an important active substance to maintain animal health. It plays an indispensable role in development and metabolism. Some substances are similar to a certain vitamin in chemical structure, and can be converted into a vitamin through a simple metabolic reaction and become a "provitamin". For example, beta-carotene can be converted to vitamin A, and 7-dehydrocholesterol can be converted to vitamin D3.

The animal body is like a complex chemical factory, constantly carrying out various biochemical reactions, which are closely related to the catalysis of biological enzymes. For enzymes to be active, coenzymes must be present. Many vitamins are known to be coenzymes or constituents of coenzymes. Therefore, vitamins are important substances to maintain and regulate the normal metabolism of the body.

1. Adjustability

Vitamins do not constitute the components of body tissues and cells, nor do they produce energy. Their role is mainly to participate in the regulation of body metabolism.

2. Trace

Animals have very little vitamin requirements, and daily requirements are often calculated in milligrams (mg) or micrograms (μg).

3. Exogenous

Most vitamins cannot be synthesized by the animal body or are not synthesized in sufficient quantities and must be obtained frequently through animal feed.

4. Specificity

Once a certain vitamin is lacking, the animal will show a characteristic morbidity.

Unlike carbohydrates, fats and proteins, vitamins are limited in natural feed ingredients. Therefore, in order to maintain the normal physiological function of animals, artificial vitamins are often added to animal feed.

According to the nutritional needs of different animals, feed enterprises generally mix various vitamins to make multi-dimensional premixes, and then mix them with other feed raw materials and feed additives to make compound feeds for animals to eat directly. Due to the development of the world's breeding industry, the current consumption of vitamins for animals far exceeds that for humans.

The ten known vitamins can be roughly divided into two categories: fat-soluble and water-soluble. Vitamin A, vitamin D, vitamin E, and vitamin K are fat-soluble vitamins, while B vitamins and vitamin C are water-soluble vitamins. After the water-soluble vitamins are absorbed through the intestinal tract, they are circulated to the tissues needed by the body. Fat-soluble vitamins are emulsified in bile and then absorbed in the small intestine, and enter into various organs in the body from the lymphatic circulatory system, and excess fat-soluble vitamins can be accumulated in the body. Vitamin A and vitamin D are mainly stored in the liver, and vitamin E is mainly stored in adipose tissue.

Although the physiological function of vitamins is very important, it is not the more the better.

Long-term intake of a large amount of vitamin A is easy to accumulate in the body, which may cause poisoning symptoms such as bone decalcification, joint disease, dry skin, and decreased feed intake.

In order to standardize the use of feed vitamins, the Ministry of Agriculture has formulated the "Specifications for the Safe Use of Feed Additives" (Ministry of Agriculture Announcement No. 1224) to set the maximum limits for vitamin A, vitamin D, vitamin K3, etc. in compound feeds to ensure animal health.